In conventional saxophones, the keys for playing the notes G.music-sharp., C.music-sharp., B and B flat form a cluster played by the fingers of the left hand. More specifically, the B and B flat notes are played by alternately pressing the respective keys with the little finger of the left hand. When playing musical selections requiring a transition between B and B flat, the little finger must slide rapidly and smoothly between two adjacent keys; otherwise an improper sound results. This transition is particularly difficult for beginning saxophonists and, with some selections, for accomplished saxophonists.
Normally the thumb of the saxophone player's left hand is placed on the thumb rest. When playing the upper register, it is used to depress a key adjacent the rest; however, when playing the lower register, it is not used except for support of the instrument.